The Scope of Contributory Liability for Copyright Infringement
Cox Communications, Inc. v. Sony Music Entertainment, 607 U.S. __ (2026)
I didn’t list contributory liability for infringement as one of the enduring non-AI issues in copyright law, but this year’s decision in Cox Communications v. Sony Music Entertainment is a reminder that issues thought to have been resolved years ago can resurface at any time.
Factual Background
Cox Communications, Inc. is an internet service provider selling internet, telephone, and cable television connections to millions of people. Some of its customers used this service to set up peer-to-peer networks such as BitTorrent to distribute copyrighted music without the permission of copyright owners. Sony Music Entertainment and other record companies owned the copyrights in some of these songs. Through the Recording Industry Association of America (RIAA), it hired a company to monitor illegal file sharing and notify internet service providers when it detected infringement. The company sent Cox Communications 163,148 notices of infringement during a two-year period. Cox Communications warned or suspended customers who were repeat infringers, but rarely terminated service for copyright infringement.
Sony and others sued Cox Communications for contributory and vicarious copyright infringement. They claimed that Cox Communications failed to take adequate measures to stop infringement, thereby inducing or materially contributing to its customers’ infringement of music copyrights.
The U.S. District Court for the Eastern District of Virginia denied Cox Communications safe harbor under the Digital Millennium Copyright Act (DMCA) and allowed the case to proceed to trial on theories of vicarious and contributory copyright infringement. The jury found Cox Communications liable on both counts and awarded $1 billion in statutory damages.
The Court of Appeals reversed the vicarious liability verdict, but affirmed the finding of willful contributory infringement. It vacated the damages award and remanded the case for a new trial on damages.
The case ultimately made its way to the United States Supreme Court. The Supreme Court unanimously reversed. Justice Thomas wrote the majority opinion. Justice Sotomayor wrote a concurring opinion.

Legal Background
Direct and Indirect Infringement
A copyright owner has the exclusive right to copy, distribute, display, perform, and make derivative works based on the copyrighted work. The exclusive right to perform a work includes the exclusive right to digitally transmit it. Anyone who exercises one of these exclusive rights without the owner’s consent is an infringer. Statutory damages of up to $150,000 per work may be awarded if infringement is willful. 17 U.S.C. § 504 (c)(2).
A person who actually performs the acts of unlawful reproduction, distribution, performance, etc. is guilty of direct infringement. A person who did not actually perform the infringing act but is responsible in some way for furthering it may be guilty of indirect infringement.
Using an internet service to which you subscribe to reproduce, distribute and transmit copies of musical works without the copyright owners’ permission is an example of direct infringement. Providing a service or facility that customers use to do that is a potential source of contributory liability for infringement, but only under certain conditions.
In this case, Sony sought to hold Cox Communications liable for indirect infringement.
Vicarious and Contributory Liability
Courts recognize two kinds of indirect infringement: vicarious and contributory.
Vicarious liability
Vicarious liability may be imposed when one person has the right and ability to control, supervise and stop another person’s activity. Because employers have this power over their employees, they are often held vicariously liable for their employees’ acts within the course and scope of the employment.
Vicarious liability for infringement requires a showing of direct financial benefit from the infringing activity to the person with supervisory control. The lower courts rejected Sony’s claim of vicarious infringement liability because the financial benefit Cox received from its customers took the form of monthly internet subscription fees. It was not directly tied to infringing activity. Subscribers paid for lawful internet access, not for the ability to infringe copyrights. Cox Communications did not profit specifically or directly from the piracy occurring in the networks its customers set up.
The only issue to reach the United States Supreme Court in this case, therefore, was whether Cox Communications could be held contributorily liable for the infringing acts of its customers.
Contributory liability
Contributory liability may be imposed when a person either induces or materially contributes to another person’s wrongful act.
Material Contribution
The common law basis for contributory liability was “material contribution.” A person could be found to have materially contributed to an activity if s/he provided the site and facilities for infringement. No proof of inducement was necessary. Napster, for example, was found to have materially contributed to users’ acts of infringement because it maintained a centralized service with a searchable index of music files for users to download.
Sony Corp. v. Universal City Studios raised the question whether a company that provides products that enable copyright infringement is always contributorily liable for “materially contributing” to users’ acts of direct infringement.
The case involved video recording products, i.e., equipment that people can use to record television programs. The Supreme Court held that recording free, over-the-air broadcasts to watch at a more convenient time is fair use, so long as the recording is made for the viewer’s own personal, noncommercial use. The Court then held that a company is not contributorily liable for infringement merely because it provides a service or product that customers can use to infringe copyrights, provided the product or service has substantial non-infringing uses. Because recording a television program for later viewing is a substantial, non-infringing use, and there was no evidence that Sony said or did anything to encourage customers to make infringing uses of its products, the Court held the company could not be held contributorily liable for infringing acts on the part of the buyers of its products. The short answer, then, is no. Merely providing a product or service that can be used to infringe copyrights will not necessarily result in contributory liability for infringement, provided it has substantial, non-infringing uses.
Inducement
The Court limited the scope of this holding (sometimes called the “Betamax safe harbor”) in Metro-Goldwyn-Mayer Studios, Inc. v. Grokster, Ltd. In this case, the Court held that a company does not get the benefit of the Betamax safe harbor for a product or service that has substantial, non-infringing uses if it actively induces infringing uses.
In Grokster, the Court relied on marketing, communications and operational evidence that Grokster had deployed promotional materials and meta-tags designed to capture internet searches for “Napster.” Napster was a file-sharing network that had been shut down after a court ordered it to block users from sharing copyrighted materials. (Napster has since been rebranded as a provider of generative and agentic AI services.) It also distributed newsletters to users touting the availability of copyrighted music and movies to download on its networks. Customer support instructed users on how to locate, download and play copyrighted files.
Even if a product or service has substantial, non-infringing uses, then, contributory liability may arise if a company actively induces infringing uses by soliciting and encouraging infringers to use it and helping customers use it to infringe copyrights.
The Issue in Cox Communications v. Sony
Two rules can be distilled from pre-2026 contributory infringement cases:
1) Furnishing a product or service may result in “material contribution” liability if its primary use is to infringe copyrights.
2) Furnishing a product or service that has substantial, non-infringing uses will not result in contributory liability unless the provider actively induces infringing uses.
The question raised in Cox Communications v. Sony Music was whether failing to stop known infringing uses is also a basis for imposing contributory liability, when the product or service has substantial, non-infringing uses.
The holding in Cox Communications v. Sony Music
The Supreme Court unanimously held that an internet service provider’s failure to stop known infringing uses of its service is not a basis for imposing contributory liability for the infringing uses that customers make of its service. An ISP’s failure to stop known infringement neither induces users’ infringement nor provides an independent, third basis for contributory liability.
The Digital Millennium Copyright Act
The Digital Millennium Copyright Act (DMCA) immunizes ISPs from contributory liability for user-provided content if they have implemented “a policy that provides for the termination in appropriate circumstances of subscribers and account holders” who are repeat infringers. 17 U.S.C. § 512(i)(1)A).
Sony basically argued that this immunity would be unnecessary if ISPs are not liable for providing services to known infringers anyway. Why try to incentivize ISPs to terminate known infringers’ accounts if they are not at risk of liability even in the absence of the DMCA?
The DMCA, however, does not expressly impose liability for providing internet service to known infringers. Another DMCA provision says that failure to comply with the DMCA’s safe harbor conditions “shall not bear adversely upon . . . a defense by the service provider . . . that the service provider’s conduct is not infringing.” 17 U.S.C. § 512(l).
To put it more colloquially, the DMCA’s safe harbor provisions are meant to be a shield, not a sword.
Intent
Although intent has never been an essential element of a copyright infringement claim, Justice Thomas interpreted the Court’s precedents as imposing an intent requirement in contributory infringement claims:
“The provider of a service is contributorily liable for the user’s infringement only if it intended that the provided service be used for infringement. The intent required for contributory liability can be shown only if the party induced the infringement or the provided service is tailored to that infringement.”
Cox Communications v. Sony Music, at 7.
Justice Sotomayor’s Concurrence
Justice Sotomayor agreed that an ISP cannot be held contributorily liable for copyright infringement unless intent is established. She filed a concurring opinion, however, to dispute that inducement and tailoring a product to infringing uses are the only two situations that may support a finding of intent. She would have held the door open for other ways of establishing intent under common law “aiding and abetting” theory.
She also criticized the majority’s interpretation of the DMCA:
“The majority’s decision thus permits ISPs to sell an internet connection to every single infringer who wants one without fear of liability and without lifting a finger to prevent infringement. It also means that Cox is free to abandon its current policy of responding to copyright infringement. [U]nder the rule the majority adopts today, the safe harbor provision will not “d[o] anything at all” going forward. . . . Congress did not enact the safe harbor just so that this Court could eviscerate it.”
Cox Communications v. Sony Music (J. Sotomayor, concurring opinion) (citations omitted) at 6–7.
Nevertheless, because she did not believe the requisite showing of intent had been made in this case, she concurred in the judgment.
Limitations
Cox Communications v. Sony Music only applies to internet service providers, what the common law described as “conduits.” It does not directly apply to people who copy, distribute or host infringing material.
Also, the Court noted that an ISP normally does not actually have knowledge of the identity of the user who is committing direct infringement. It has records of IP addresses associated with accounts, but a single IP address might be used by multiple people, not all of whom are infringers. It is possible that in a different case, where the defendant actually does know the identity of the specific direct infringer, the requisite finding of intent might be easier to make. Future cases will need to flesh that out.
Implications
As Congress and courts grapple with emerging generative AI copyright issues, it is likely that attempts will be made to apply the principles announced in Cox Communications v. Sony Music to generative AI architecture. While the internet is a neutral data conduit, large language models that drive generative-AI function by ingesting massive datasets of protected works to optimize their commercial output. Rights holders argue that building a system dependent on unauthorized ingestion constitutes direct or secondary infringement. However, the intent requirement articulated in Cox provides AI developers with a potentially expansive defense to output infringement. If providing a tool with the simple knowledge that users may generate infringing outputs is legally insufficient, then the battleground over generative AI must shift. Because generative AI tools arguably have substantial, non-infringing uses, litigators will need to prove intent to induce infringement to prevail on a contributory output infringement claim. The potential impact on input infringement claims, of course, is a different matter.
We are already seeing this defense framework reshape federal dockets. In June 2026, tech platforms seized upon the Cox precedent to try to stop copyright claims at the pleadings stage. In a motion filed in Tennessee federal court, X Corp. invoked Cox v. Sony Music to argue that music publishers’ secondary liability claims must be dismissed, asserting that the plaintiffs failed to allege explicit “affirmative inducement” rather than general platform piracy.
Practical Tip
Despite the Court’s ruling in Cox Communications v. Sony Music, platform providers may find it prudent to continue to comply with DMCA safe harbor requirements. Not only could this help them qualify for the immunities the DMCA provides, but it might also help demonstrate a lack of infringing intent.

